Update admin_methods_test.py
Update admin_methods_test.py

Add tests for list_approved_developers() throwing an exception for anonymous and non-admin requests.
kbase/catalog,kbaseIncubator/catalog,kbase/catalog,kbase/catalog,kbase/catalog,kbase/catalog,kbaseIncubator/catalog,kbaseIncubator/catalog,kbaseIncubator/catalog,kbaseIncubator/catalog,kbase/catalog